1. Field of the Invention
The present invention relates to vehicle sun visors, and in particular to vehicle sun visors having a visor body and a support rod provided on the visor body for engagement with a support hook mounted to a vehicle cabin ceiling.
2. Description of the Related Art
A known vehicle sun visor has a visor body as a major element. The visor body is rotatably supported by a horizontal rod portion of a first support rod that is supported on a vehicle cabin ceiling via a bracket. Therefore, the visor body can move between a storage position along the vehicle cabin ceiling and a light-shielding position along a windshield as the visor body rotates relative to the horizontal rod portion of the first support rod.
In order to enable the visor body to stably rotate, there has been proposed to provide a second support rod at a predetermined position. The second support rod has the same axis as the horizontal rod portion of the first support rod and is rotatably engageable with a support hook mounted to the vehicle cabin ceiling.
In general, the second support rod includes a core rod member and a tubular outer sleeve disposed on the outer peripheral side of the core rod. The outer sleeve is typically constituted by first and second sleeve halves that are joined to each other at their joint surfaces, for example, by utilizing a high frequency or ultrasonic welding technique, or by an adhesive agent, in order to configure the second support rod.
However, if the first and second sleeve halves are joined at the joint surfaces by welding, it is likely that weld flash may be formed so as to extend beyond the joint surfaces. Similarly, if an adhesive agent joins the first and second sleeve halves at the joint surfaces it is likely that a part of the adhesive agent extends to the outside of the joint surfaces.
In order to prevent the formation of weld flash, Japanese Laid-Open Patent Publication No. 2002-192948 proposes to form a claw-like engaging projection on the first sleeve halve and to form a mating engaging portion on the second sleeve halve for engagement with the engaging projection.
However, using this construction of forming the engaging projection on the first sleeve halve and forming the mating engaging portion on the second sleeve halve, there is a possibility that the outer sleeve, formed by the first sleeve halve and the second sleeve halve thus constructed, may be displaced in the radial direction relative to the core rod member. In addition, if displacement prevention portions are formed on the first and second sleeve halves, the construction of the outer sleeve may become complicated. Furthermore, the first and second sleeve halves must be molded separately by using differently configured molds.